If you'd like an overview of the "best long fast lenses for action photographers" you could do worse than read this article over at BJP. As interesting, perhaps, were their words regarding the way glass has to be produced in batches and the way that variations in those batches can actually result in design tweaks as each batch of lenses are produced. For example:

In the case of Zeiss, details have been released in the past showing that 100 units of production lenses will be backed up by 10 sets of glass held as repair components. Because the same glass cannot be repeated exactly, these high-end apochromatic telephotos can only be repaired while this stock lasts.